In recent times, the demand of super-miniaturized and high-capacity semiconductor memories is rapidly increasing in response to a miniaturization and a higher-performance of electronic appliances and the increasing demand of mobile products. Generally, a variety of methods for increasing storage capacity of semiconductor memories have been widely used. First, one method for increasing storage capacity of semiconductor memories is to increase the integration degree of semiconductor chips. Second, another method for increasing storage capacity of semiconductor memories is to populate and assemble a plurality of semiconductor chips into a single semiconductor package.
The method of increasing storage capacity of semiconductor memories requires much more efforts and costs and much longer time. However, the method of increasing the integration degree of semiconductor chips is able to easily increase storage capacity of semiconductor memories by changing only the packaging method.
In addition, the method of increasing the integration degree of semiconductor chips is more advantageous than the method of increasing storage capacity of semiconductor memories in terms of costs, efforts, and time consumed in development and research environments. As a result, manufacturers of semiconductor memories have made efforts to increase storage capacity of semiconductor memory devices through multi-chip packaging in which multiple semiconductor chips are populated on a single semiconductor package.